UPDATE:

Well I couldn't get Macplay for OSx. I downloaded it only to discover it was for classic. No thanks. Haha!

However, I do have GREAT NEWS! As I was looking for other MP3 players (as suggested by GefallenenEngel), I found utilities for splitting MP3 files. I took a chance and figured whatever code is keeping iTunes from bringing the file over might be taken out....if the file is split up into parts. In other words, if the file is corrupt in some kinda way I would find out if I split it up - and see if the trouble is just one part, or the whole.

I downloaded Xmp3split (version 1.0) for OSX.

I used it as is, I didn't go into the preference folder and check what length of file I wanted split, so it did it for me. 136 files of 7 minute chunks. The original file was 499.5 MB, so it was a lot.

SUCCESS!

I can now play the file that iTunes couldn't open. I selected them and sent them over to iTunes with ease. I guess now that I have all the files in iTunes I should join them back into one. But currently I'm just happy to have this right now. More on the post progress later.

I have several files that iTunes never picked up. I'll see if splitting and joining them back into MP3 files will help do the trick. Perhaps others will pick up on this trick.

Thanks for the help, and inspiration. Glad there is peer-to-peer support on these forums.